High-temperature shock consequences on the red flour beetle (Tribolium castaneum) and the rice weevil (Sitophilus oryzae).

Temperature shocks have profound effects on biological and physiological functions at all levels of organization. However, the recovery periods from these shocks and their subsequent impacts remain unknown. Herein, our study investigated the effect of short temperature stress on survival, dormancy recovery time, nutritional indices, life traits and development rate for T. castaneum (larvae and adults) and S. oryzae adults. The results showed significant effects on survival rates of T. castaneum (larvae and adults) and S. oryzae adults. When both insects had been exposed to high-temperature shock, survival rates decreased with higher temperatures and longer periods of exposure. Furthermore, recovery times varied between and within the insect species, as prolonged exposure to thermal shocks increased recovery periods. Moreover, dormancy time resulting from the high-temperature shocks significantly affected food deterrence and food intake, regardless of the stage of development, species, exposure periods and temperature-exposure conditions. Subsequently, differences in body growth rates and food consumption rates are an appropriate indicator of differences in food conversion rates under high-temperature shocks, regardless of the species and developmental stages. On the other hand, our results indicated that as high-temperature shocks increased, the total development period increased of T. castaneum. Likewise, the pupal stage increased with increasing high-temperature shocks, and the larval stage decreased with increasing thermal shocks and increasing the periods of exposure. In summary, our study showed the importance of dormancy recovery time and its subsequent effects for improving disinfestation effectiveness of heat treatment, and understanding insect response to high temperatures.

The impact of COVID-19 on the occupational health of oncologists: a descriptive analysis of occupational safety, perceived burnout and social support among practicing oncologists in Alexandria, Egypt.

BACKGROUND: Healthcare workers, including oncologists, face a higher potential risk of contracting coronavirus disease 2019 (COVID-19) while managing patients. Moreover, the uncertainty that came with COVID-19 and its associated social stigma may worsen what was already a crisis (burnout) among oncologists. Data are scarce on the impact of COVID-19 on the occupational health and safety of oncologists in low and middle-income countries. METHODS: We conducted a cross-sectional survey in February 2021 to evaluate the impact of COVID-19 on practicing oncologists in Alexandria governorate, Egypt. An anonymised self-reporting questionnaire was electronically distributed to 88 participants to collect information on occupational safety at work, the prevalence of COVID-19 among respondents and the impact of COVID-19 on their wellbeing, including perceived burnout and family support. RESULTS: Out of the 88 contacted oncologists, 75% completed the survey. The mean age of participants was 34.79 years (SD ± 10.42), of which 45% were residents, 36% were specialists and 18% were consultants. Most of the oncologists (58% of 66) felt they were not adequately protected against COVID-19. The majority (78% of 66) have managed COVID-19 infected cancer patients, and 76% (out of 66) had experienced COVID-19 like symptoms. A third (n = 21) of the respondents were confirmed COVID-19 infected: 62% of the latter thought they were infected at the workplace, either by a patient or a colleague. The majority of the oncologists (78%) perceived being more overwhelmed or burned out than in the pre-COVID-19 era. Nearly half of the participants (48%) reported their family members and friends had reduced contact with them despite being COVID-19 negative, in fear of being infected. The burnout was significantly higher in those lacking family support than those who had, 52% versus 28% respectively (p = 0.038). CONCLUSIONS: One-third of practicing oncologists were diagnosed with COVID-19, and most thought they were infected at the hospital. Occupational safety measures, including mental health programs, need to be improved with special emphasis on the role of family support in mitigating perceived burnout among practicing oncologists.

Low temperature shock and chill-coma consequences for the red flour beetle (Tribolium castaneum) and the rice weevil (Sitophilus oryzae).

Insects face several (environmental) abiotic stressors, including low temperature, which cause the failure of neuromuscular function. Such exposure leads insects toa reversible comatose state termed chill-coma, but the consequences of this state for the organism biology were little explored. Here, the consequences of the chill-coma phase were investigated in two of the main stored product pest species - the red flour beetle Tribolium castaneum (larvae and adults) and the rice weevil Sitophilus oryzae (adults). For this purpose, a series of low-temperature shocks were used to estimate the chill-coma recovery time (CCRT), survival, nutrition and weight gain/growth of T. castaneum (larvae and adults) and S. oryzae, as well as the development of T. castaneum life stages. The relatively long CCRT was characteristic of beetle larvae, at different low-temperature shocks, and CCRT increased with decreasing temperatures and increasing exposure intervals for both pest species. The survival was little affected by the low-temperature shocks applied, but such shocks affected insect feeding and growth. Tribolium castaneum larvae was more sensitive than adults of both insect species. Moreover, the relative consumption and weight gain of S. oryzae adults were lower than those of T. castaneum adults and mainly larvae, while feeding deterrence was not affected by low temperature shocks, unlike food conversion efficiency. Low-temperature shocks, even under short duration at some temperatures, significantly delayed development. The lower the temperature and the higher the exposure period, the more delayed the development. Thus, the physiological costs of chill-coma are translated into life-history consequences, with potential implications for the management of this insect pest species in stored products and even more so on red flour beetles and rice weevils.

Pimpinella anisum Essential Oil Nanoemulsion Toxicity against Tribolium castaneum? Shedding Light on Its Interactions with Aspartate Aminotransferase and Alanine Aminotransferase by Molecular Docking.

The insecticidal activity is the result of a series of complex interactions between toxic substances as ligands and insect's enzymes as targets. Actually, synthetic insecticides used in pest control programs are harmful to the environment and may affect non-target organisms; thus, the use of natural products as pest control agents can be very attractive. In the present work, the toxic effect of aniseed (Pimpinella anisum L.) essential oil (EO) and its nanoemulsion (NE) against the red flour beetle Tribolium castaneum, has been evaluated. To assess the EO mode of action, the impact of sub-lethal concentrations of aniseed EO and NE was evaluated on enzymatic and macromolecular parameters of the beetles, including aspartate aminotransferase (AST), alanine aminotransferase (ALT), total protein, total lipids and glucose. Finally, a molecular docking study was conducted to predict the mode of action of the major EO and NE components namely E-anethole, Limonene, alpha-himalachalene, trans-Verbenol and Linalool at binding site of the enzymes AST and ALT. Herein, the binding location of the main compounds in both proteins are discussed suggesting the possible interactions between the considered enzymes and ligands. The obtained results open new horizons to understand the evolution and response of insect-plant compounds interactions and their effect predicted at the molecular levels and side effects of both animal and human.

A Life Table for Liriomyza trifolii (Diptera: Agromyzidae) in a Temperate Zone of Northeast Egypt With Key Factor Analysis.

The American serpentine leaf miner, Liriomyza trifolii (Burgess) (Diptera: Agromyzidae), is a perennial pest of leguminous crops in the Mediterranean region. A life table was constructed for L. trifolii infesting broad bean, Vicia faba L., in northern Egypt. Key factor analysis was used to rank sources of immature mortality over two seasons. Leaf miners had three successive generations, and a partial fourth, in each year, with peak abundance in March-April. Less than 15 and 22% of L. trifolii survived to adult in seasons one and two, respectively. The largest contributor of immature leaf miner mortality in both seasons was unknown (41.2 and 39.1% of total mortality, respectively), and likely comprised a combination of abiotic factors, parasitoid-inflicted mortality (host-feeding), and predation. Parasitism was second, contributing 36.2 and 35.6% of total mortality in the two seasons, respectively, primarily due to larval parasitism by Diglyphus isaea (Walker) (Hymenoptera: Eulophidae), and low levels of larval-pupal parasitism by Opius pallipes Wesmael (Hymenoptera: Braconidae) and Halticoptera circulus (Walker) (Hymenoptera: Pteromalidae). Residual mortality resulted from malformed pupae or failed adult emergence. Key factor analysis revealed malformation to be the major cause of pupal mortality. Sequential regression confirmed that unknown mortality and D. isaea were the top stage-specific factors, both acting on larvae. Parasitoid abundance tracked host abundance across generations, but density dependence was not observed for any mortality factor, and the magnitudes of regression slopes were small. The results indicate the potential importance of conservation biological control in management of L. trifolii, given that naturally occurring parasitoids and other biotic/abiotic factors exert significant mortality on immature leaf miners.

When Predators Avoid Predation by Their Con- and Heterospecific Competitors: Non-consumptive Effects Mediate Foraging Behavior and Prey Handling Time of Predators.

Aphids show highly aggregated distributions, and thus their predators tend to aggregate as well, creating conditions optimal to consumptive and non-consumptive (N-CEs) effects among competing predators, both conspecific and heterospecific. If predatory larvae are themselves potential prey for other predators, they may be also sensitive to N-CEs imposed by their con- or heterospecifics. A partitioned Petri-dish that permitted the passage of visual and chemical signals was used to examine the N-CEs of predator on foraging behavior of other predators, as prey themselves. Functional responses of second-instar Chrysoperla carnea Stephens (Chrysopidae: Neuroptera) and third-instar Coccinella undecimpunctata L. (Coccinellidae: Coleoptera) to Aphis craccivora Koch. (Aphididae: Hemiptera) in the absence and presence of predation threat were derived. Both predators responded to presence of competitor signals with declined consumption, but lower attack rate and longer handling time were evident for C. undecimpunctata. The functional response type of second-instar C. carnea did not alter, even in the presence of larger heterospecifics, remaining a type 2 functional response in all treatments, but that of third-instar C. undecimpunctata did under the predation risk of third-instar C. carnea. Therefore, the third-instar C. undecimpunctata appeared to have suffered foraging costs (longer handling time and lower attack rate) under predation risk of C. carnea, but second-instar C. carnea did not. If predatory larvae of both species are synchronized in the same aphid patch, C. undecimpunctata might leave the patch to minimize its own risk of being preyed upon, or at least search at reduced rates. Thus, N-CEs may signify be biologically significant.